PF9601N is a propargylamine-containing irreversible monoamine oxidase B inhibitor (MAOBI) previously identified by our group in an extensive screen of potential MAOIs. Besides its potent inhibitory capacity, it possesses several neuroprotective properties demonstrated in different animal and cellular models of Parkinson's disease (PD). The beneficial effects of PF9601N, which have been related to the propargylamine group present in the molecule, are mediated through actions in pathways that are commonly involved in the neurodegeneration observed in other neurodegenerative disorders such as Alzheimer's disease (AD), thus making this molecule a promising agent in the therapy of this disease as well. Thus, to study the beneficial properties of PF9601N in depth, we investigated its effects against an in vivo model of excitotoxicity, an important mechanism involved in the neuronal damage observed in neurodegenerative diseases. The finding that PF9601N was able to prevent the induced excitotoxic damage by decreasing the evoked release of excitatory neurotransmitters and decreasing the output of the inhibitory and neuroprotective taurine as well as preventing the induced glial activation and apoptosis gave more value to this compound to be considered in the therapy. The current treatment for AD is the use of cholinesterase inhibitors (ChEIs) although there is also a NMDA receptor antagonist. However, far from stopping the disease's progression, these drugs only produce a temporary symptomatic benefit, thus highlighting an urgent need to provide real disease-modifying drugs. At present, the most accepted notion is that AD is a multifactorial disease caused by many different factors and thus drug therapy with multifunctional compounds, the so-called multi-target-directed ligand (MTDL) approach, embracing diverse biological properties will have noticeable advantages over individual-target drugs or cocktails of drugs. In this context, this thesis focuses on the structure-activity relationship (SAR) study and the biological evaluation of different hybrid compounds specifically designed and synthesised to target multiple factors involved in AD. The hybrid molecules combine the benzyl piperidine moiety of Donepezil, a commonly used anticholinesterasic for the treatment of AD, with the propargylamine or the indolyl propargylamine substructure of PF9601N, with the aim of retaining the MAO inhibitory capacity as well as the neuroprotective and antiapoptotic properties observed for this compound. The work presented in this thesis demonstrates that some hybrid compounds are potent MAOIs (nM range) and moderately potent ChEIs (submicroM range). Among them, ASS234 has also been shown to reduce Αβ fibrillogenesis, and to protect neuronal cells from A and H2O2 toxicity. Thus, this compound has proved to be able to block the Aβ-induced cell death in two ways: by preventing caspase cleavage and activation and blocking LDH release. Overall, the present data suggest ASS234 as a promising MTDL that may have a potential disease-modifying role in the treatment of AD since it is able to interact with diverse targets involved in the pathogenesis underlying AD.